We welcome retro users & hardware gurus alike! Come and join the party :)
https://www.exxosforum.co.uk/forum/
It is extremely low resistance, you're right, and having read the latest posts it wouldn't be suitable as it'd likely just short the contacts.PhilC wrote: 28 Feb 2024 19:23 That tape is quite a low resistance. We use it at work for boiler lagging.
What about conductive painting the surfaces?
The decomposing PVC foam has released chlorine which has attacked the aluminium coating on the back of the mylar. If this hadn't happened then irrespective of the foam degradation the keys would still work.rubber_jonnie wrote: 29 Feb 2024 09:40It is extremely low resistance, you're right, and having read the latest posts it wouldn't be suitable as it'd likely just short the contacts.PhilC wrote: 28 Feb 2024 19:23 That tape is quite a low resistance. We use it at work for boiler lagging.
What about conductive painting the surfaces?
Interesting subject though. Would it be feasible to use the old foil discs, or are they too far gone?
Interesting stuff, looking forward to seeing your results.stephen_usher wrote: 29 Feb 2024 10:39The decomposing PVC foam has released chlorine which has attacked the aluminium coating on the back of the mylar. If this hadn't happened then irrespective of the foam degradation the keys would still work.rubber_jonnie wrote: 29 Feb 2024 09:40
It is extremely low resistance, you're right, and having read the latest posts it wouldn't be suitable as it'd likely just short the contacts.
Interesting subject though. Would it be feasible to use the old foil discs, or are they too far gone?
The emergency thermal blanket material is identical to the original disc material, so you just need to cut out disc of that and stick it to some foam (with the aluminium coating away from the PCB). It's the foam which is proving to be the trickiest item to source.
I should have some 3mm thick, 12mm wide weather proofing foam with adhesive on both sides arriving this afternoon and I can cut discs from that using the 11mm hollow punch I've obtained.
What I may try doing is sticking a strip of mylar on top of the foam strip and then punching the disc out as a single unit rather than doing them individually and sticking them together afterward.
Sounds like a good thing to try.stephen_usher wrote: 29 Feb 2024 11:36What I may try doing is sticking a strip of mylar on top of the foam strip and then punching the disc out as a single unit rather than doing them individually and sticking them together afterward.
Of course these capacitative pads aren't just used by Apricot, Apple Lisas have the same. So if I work out an easy way to produce them then that benefits the whole community.PhilC wrote: 29 Feb 2024 11:54 I admire your commitment to getting these old computers fixed Stephen. Apricon certainly did come up with some interesting technology back in the day.